Jennifer Macalady

Jennifer Macalady

Understanding the workings of these biofilm systems offers clues to how early life evolved, says Macalady, associate professor of geosciences. And, in addition to being windows onto Earth's history, these environments "have turned out to be really extraordinary model ecosystems for microbial ecology in general."

Deep inside the Frasassi cave system in Italy and more than 1,600 feet below the Earth's surface, divers found filamentous ropes of microbes growing in the cold water, according to a team of Penn State researchers. "Sulfur caves are a microbiology paradise. Many different types of organisms live in the caves and use the sulfur," says Jennifer L. Macalady, assistant professor of geosciences. "We are trying to map which organisms live where in the caves and how they correspond to the geochemical environment."